#include <stdint.h>
#ifndef __DICT_H
#define __DICT_H

#define DICT_OK 0
#define DICT_ERR 1

#define DICT_NOTUSED(V) ((void) V)

/* Hash表中的实体Entry */
typedef struct dictEntry {
    void *key;
    union {
        void *val;
        uint64_t u64;
        int64_t s64;
    } v;
    struct dictEntry *next;
} dictEntry;

/* Hash中常用的Hash函数以及Key, Value的拷贝, 比较, 析构函数 */
typedef struct dictType {
    unsigned int (*hashFunction)(const void *key);
    void *(*keyDup)(void *privdata, const void *key);
    void *(*valDup)(void *privdata, const void *obj);
    int (*keyCompare)(void *privdata, const void *key1, const void *key2);
    void (*keyDestructor)(void *privdata, void *key);
    void (*valDestructor)(void *privdata, void *obj);
} dictType;

/* Hash Table, 两个表是为了实现增量渐进Hash */
typedef struct dictht {
    dictEntry **table; /* 采用链式Hash表的方式 */
    unsigned long size; /* Hash Table的大小 */
    unsigned long sizemask; /* 基于size的掩码 */
    unsigned long used; /* Hash Table使用的Entry数目 */
} dictht;

/* 真正的Hash表 */
typedef struct dict {
    dictType *type;
    void *privdata; /* privdata */
    dictht ht[2]; /* 实现渐进Hash */
    int rehashidx; /* -1表示没有进行渐进Hash */
    int iterators; /* 当前运行迭代器的数目 */
} dict;


/* 1表示迭代器安全, 可以调用Hash表的所有API; 否则只能调用dictNext函数*/
typedef struct dictIterator {
    dict *d;
    int table, index, safe;
    dictEntry *entry, *nextEntry;
    long long fingerprint; /* 计算Hash表的状态 */
} dictIterator;

typedef void dictScanFunction(void *privdata, const dictEntry *de);

/* 初始大小 */
#define DICT_HT_INITIAL_SIZE 4

/* Macros */

/* dict释放Val */
#define dictFreeVal(d, entry) \
    if ((d)->type->valDestructor) \
        (d)->type->valDestructor((d)->privdata, (entry)->v.val)

/* dict设置Val */
#define dictSetVal(d, entry, _val_) do { \
    if ((d)->type->valDup) \
        entry->v.val = (d)->type->valDup((d)->privdata, _val_); \
    else \
        entry->v.val = (_val_); \
} while (0)

/* dict设置有符号整型 */
#define dictSetSignedIntegerVal(entry, _val_) \
    do { entry->v.s64 = _val_; } while (0)

/* dict设置无符号整型 */
#define dictSetUnsignedIntegerVal(entry, _val_) \
    do { entry->v.u64 = _val_; } while (0)

/* dict释放Key */
#define dictFreeKey(d, entry) \
    if ((d)->type->keyDestructor) \
        (d)->type->keyDestructor((d)->privdata, (entry)->key);

/* dict设置Key */
#define dictSetKey(d, entry, _key_) do { \
    if ((d)->type->keyDup) \
        entry->key = (d)->type->keyDup((d)->privdata, _key_); \
    else \
        entry->key = (_key_); \
} while (0)

/* dict比较Key */
#define dictCompareKeys(d, key1, key2) \
    (((d)->type->keyCompare) ? \
        (d)->type->keyCompare((d)->privdata, key1, key2) : \
        (key1) == (key2))


#define dictHashKey(d, key) (d)->type->hashFunction(key)
#define dictGetKey(he) ((he)->key)
#define dictGetVal(he) ((he)->v.val)
#define dictGetSignedIntegerVal(he) ((he)->v.s64)
#define dictGetUnsignedIntegerVal(he) ((he)->v.u64)

/* 获取总共的size */
#define dictSlots(d) ((d)->ht[0].size + (d)->ht[1].size)
/* 获取总共的used */
#define dictSize(d) ((d)->ht[0].used + (d)->ht[1].used)
#define dictIsRehashing(ht) ((ht)->rehashidx != -1)

/* API */
dict *dictCreate(dictType *type, void *privDataPtr);
int dictExpand(dict *d, unsigned long size);
int dictAdd(dict *d, void *key, void *val);
dictEntry *dictAddRaw(dict *d, void *key);
int dictReplace(dict *d, void *key, void *val);
dictEntry *dictReplaceRaw(dict *d, void *key);
int dictDelete(dict *d, const void *key);
int dictDeleteNoFree(dict *d, const void *key);
void dictRelease(dict *d);
dictEntry * dictFind(dict *d, const void *key);
void *dictFetchValue(dict *d, const void *key);
int dictResize(dict *d);
dictIterator *dictGetIterator(dict *d);
dictIterator *dictGetSafeIterator(dict *d);
dictEntry *dictNext(dictIterator *iter);
void dictReleaseIterator(dictIterator *iter);
dictEntry *dictGetRandomKey(dict *d);
void dictPrintStats(dict *d);
unsigned int dictGenHashFunction(const void *key, int len);
unsigned int dictGenCaseHashFunction(const unsigned char *buf, int len);
void dictEmpty(dict *d);
void dictEnableResize(void);
void dictDisableResize(void);
int dictRehash(dict *d, int n);
int dictRehashMilliseconds(dict *d, int ms);
void dictSetHashFunctionSeed(unsigned int initval);
unsigned int dictGetHashFunctionSeed(void);
unsigned long dictScan(dict *d, unsigned long v, dictScanFunction *fn, void *privdata);

/* Hash table types */
extern dictType dictTypeHeapStringCopyKey;
extern dictType dictTypeHeapStrings;
extern dictType dictTypeHeapStringCopyKeyValue;

#endif